Stadium Seat Design Patent Infringement Lawsuit: Penghang Zhuang Schedule A Case No. 1:26-cv-11811
Penghang Zhuang Files a Federal Design Patent Lawsuit on September 28, 2026, in the Northern District of Illinois – Portable Stadium Seats, U.S. Design Patent D981,123, and Docket Updates
Penghang Zhuang filed a federal design patent infringement lawsuit on September 28, 2026, in the U.S. District Court for the Northern District of Illinois. The lawsuit concerns alleged infringement of U.S. Design Patent No. D981,123, titled Chair, which protects an ornamental design associated with a portable stadium seat.
The lawsuit was filed against defendants identified through Schedule A, a format commonly used in intellectual property enforcement actions involving multiple online sellers and e-commerce businesses.
According to the complaint analysis, Zhuang alleges that portable stadium seats offered through Amazon storefronts have substantially similar ornamental appearances to the patented design.
The specific accused products, defendant identities, and infringement allegations should be confirmed through the complaint and supporting exhibits.
Case Information
Plaintiff: Penghang Zhuang
Defendants: Defendants Identified on Schedule A
Court: U.S. District Court for the Northern District of Illinois
Case No.: 1:26-cv-11811
Date Filed: September 28, 2026
Presiding Judge: Hon. Sara L. Ellis
Nature of Action: Design Patent Infringement – 35 U.S.C. § 271 (Patent Act)
Patent at Issue: U.S. Design Patent No. D981,123 – Chair
Patent Issue Date: March 21, 2023
Reported Products at Issue: Portable stadium seats featuring backrests, seat cushions, and integrated storage compartments.
Case Update: On September 28, 2026, Penghang Zhuang filed a patent infringement complaint with supporting exhibits, including Schedule A, the asserted patent, infringement comparisons, test-purchase records, joinder evidence, and materials concerning alleged repeated infringement.
A separate case-tracking source records a motion concerning miscellaneous relief filed September 28 and an order entered October 6, 2026. The substance and effect of that order have not been independently confirmed.
The available public records do not establish the outcome of the infringement of claims or whether any temporary injunctive relief was granted.
About the Plaintiff
Penghang Zhuang is an individual patent holder identified as the plaintiff in this federal design patent infringement action.
According to the complaint analysis, Zhuang asserts rights associated with U.S. Design Patent No. D981,123, which concerns the ornamental appearance of a chair designed for use as a portable stadium seat.
The patented design reportedly includes a rectangular backrest and seat cushion, together with distinctive storage features positioned beneath the front of the seat.
Design patents protect the ornamental appearance shown in the patent drawings rather than the general function of a product. Accordingly, the infringement dispute concerns the overall visual appearance of the accused stadium seats compared with the claimed design.
The plaintiff alleges that certain products offered by online sellers embody the same or substantially similar overall ornamental appearance as the patented design.
Those allegations remain subject to judicial determination.
Monitor the Case
Public case information for Penghang Zhuang v. Defendants Identified on Schedule A, Case No. 1:26-cv-11811, is linked through PacerMonitor.
PacerMonitor provides access to federal court case information, although certain documents and features may require registration or payment. Court filings and case status may change over time.
The allegations are claims made by the plaintiff and do not, by themselves, establish liability.
Named in a Schedule A Lawsuit?
If your online store or business has been identified as a defendant in a Schedule A lawsuit, Rotek Law can assist in reviewing the allegations, evaluating potential legal options, and discussing possible resolutions.
Our team can help you understand the claims against your business and determine appropriate next steps. You may also explore our legal services for more information about our intellectual property practice.
Contact Us: +1 (305) 731-2593 Email: info@roteklaw.com
More Intellectual Property Case Updates
Stay informed about other Schedule A lawsuits, intellectual property disputes, and legal developments affecting online businesses.
Disclaimer
This page is provided for general informational purposes only and does not constitute legal advice. Case information may change as court proceedings develop. Readers should verify current case details through official court records. Viewing this page or contacting Rotek Law does not establish an attorney-client relationship.
Comments